Electric iron



Aug. 28, 1928.

ATTORNEY f y *1,682,467 C. B. BACKER ELECTRIC IRON Aug. 28, 1921s;y

Filed June 16 1926 2 Sheets--Sheet` 2 Hy a;

.f5 INVENTOR l ATTORNEY vide a heating unit for electrically heatingthe sad iron, which shall have a'high thermal Patented Aug. 28, 192s.

UNITED sTATiazs lPirrrsN'r OFFICE.

CHRISTIAN B. BACKER, 0F BROOKLYN, NEW-YORK.

EI'JIMIIIRIC IRON.

Aiaplieatin mea :une is,

My invention relates to electrically heated devices and particularly to electrically heated sad irons. l Y

An object of myinvention'is to provide an electrically heated sad iron that is simple in construction and in manufacture. Y

Another object of my invention is toprovide an electrically heated-sad iron having a heating unit that can be easily manufactured, and which will be in close thermal en agement with the portion to be heated.

other object of my invention is to proconductivity and have long` life.

I yAnother ob'ect of my invention is to provide an electrically heated sad iron that shall operate at substantially constant temperav ture.

In practicing my invention, I 'provide an electrically heated sad iron comprising a body portion and a cover member having aV handle attached thereto in a manner well known in the4 art. The body portion comrises a pressing casting, an encased heatmg -elemept located in close thermal relation with the pressing casting, terminal members, a thermally actuable device for controlling the temperature of the pressing casting and a single member for supporting the terminals, for maintaining the heating element in close thermal relation with the pressing casting and for maintaining the therma lation therewith.

In theaccompanying drawings,

Figure 1 is a view, in longitudinal vertical cross section, of a device embodying my in vention, Y "f j I Y Fig. 2 lis a plan view of the body portion actuable device in `operative re "of the device illustrated in Fig.' 1, i'

Fig. 3 is a view, in vertical lateral section, ofthe device illustrated in Fig. 1, taken on' body portion 12, a cover member 13 and a" handle 14 attached vthereto by straps 15 and secured to the cover member 13 in any manner well known in the art. I e

The body portion 12 comprises a pressing 1926. Serial No. 116,268;

casting 16, a tubular. heating element 17, a plurality of vterminal members 18 therefor,

a thermally actuable 'control switch 19 and i a clamping member 21.l An opening 22 is provided in the rear portion of the cover member 13 whereby the terminal members 18 may be brought out from the member 21.

An insulating bushing 23 is provided to inulae)l the terminal 18 from the cover mem er Y 'Ihe pressing casting 1.6 is a one-pieceV structure having a peripheral groove 25 located 1n the upper surface thereof wherein the heating element lis located. The rear portion of the pressing member 16fhas a cir- -cular recess 26 extending downward towards the ironing surface 27 of the casting member 16, and a circular shoulder 28 is provided therein whereon the thermostat 19 is supported. The edge 29. of the casting member 16 is so bevelled that the casting member presents a neat appearance. The surfaces 27 and 2 9 are ground `and polished to conform `with thepolished cover member 13 vand also to provide a surface that will permit of gulck disposal of heat' tol material to be lroned. tapped hole 31 'is' provided in Vthe top central portion of the casting mem,-

ber 16 wherein a-stud32 may be inserted to hold the clampingmember 21 and the cover member 13m operativerelation with the casting member 16. Y

is plated with a coating of copper and then with a-coating. of nickel. The presence of the coating of nickel on the surfaces 27 and v29 serve to provide a highly polished metal., lic surface .and the presence of the copper and nickel coatings'in the groove 25 serves The surface 27 of the casting member 16 l to provide a good thermal contact surface for the heating unit V17, as the thermal conductivity of the copper and nickel surface is higher than the conductivity of the cast iron comprisingthe casting member 16. By reason of the electro-plated surface of the groove 25, a greater amount of heat may be conducted from the heatingunit 17 thereby `allowingthe heating unit 17 to be operated at a lower temperature while still obtaining a desired temperature at the pressing s urface. The heating unitl will, therefore, have a longer life'. Y l

The tubular heating member 17 comprises metal tubular member 30, aV metallic sheet or helix of initially metallicmagnesium 33 a helically wound .resistor member 34, and

rality of contact members 37 insulatedly mounted thereon, a substantially circular l5`bimetal disc 38 and a plurality of contact members 39 insulatedly mounted on the disc, corresponding Vin 'number to the contact members 37. The disc 38 issupported from the base 36 by a single central stud 41, a lock nut 42 being provided to secure the stud in properly adjusted position. A plurality of terminal members 43 are insulatedly mounted on the upper surfaceof the base member 36 flexbile conductors 44 connecting the terminals g 43 to one of the contact pinsv 18 and to one of the terminals 35. The general construction of the thermally actuable switch 19 is disclosed and claimed in Patent No. 1,561,437.

The terminal pins 18 are supported by a rear portion 4 5 of the clamping member 21, that is bent angularly downwardly. Nuts 46 and' 47 and insulating bushings 48 are provided on the p-ins 18 to securely clamp them on' the portion 45. i

The clamping member 21 is substantially triangular in contour and is provided with a depending peripheral portion, shown more particularly in Fig. 3, to securely and resilientlv clamp the heating unit in the groove 1 An integraldepending portion 49 has its end engaging the base plate 36 of the switch assembly 19 to securely and resiliently hold it in the recess 26 and against the shoulder portion 28. A nut 51 on the stud 32 holds the clamping member 21 in its proper Voperative position and a nut 52 holds the cover member 13 tightly against the upper peripheral edgeof the casting 12.

The heat generated in the resistor 34 by the passage of an electric current therethrough, is quickly conducted to the tube 30, and from there' tothe walls of the grooves 25, from where it is distributed through the pressing casting 16 and to the operating surface 27. By properly locating the groove 25 in the member 16, I obtain a uniform distri- Y bution of the heat over the surface 27. I iind also that the close engagement between the 60 outer surface of the tube 30 and the casting 16 ensures a very low drop -in temeprature therebetween, and the result is that the )heat generated in the heating unit will flow to theV operating surface 27, with but little drop,

o6 when and as needed during' use of the iron,

' The disc 38 is sovlocated as to be subjected to the heat of the lower portion of the casting, that is, it will be actuated more particularly by, or in accordance with, the temperature of the Voperating surface 27.V Automatic control of the energization of the heating unit will thus be effected in accordance with' the temperature of the ironing surface 27 and therefore in accordance with the demands made on the iron during operation thereof.

While I have illustrated and described a.

Vheating unit comprising a tubular member,

I do not desire to be restricted thereto, as I may omit the tube and secure the resistor member and enclosing layer of magnesium oxide in .the groove 25 in the manner d'e- Y scribed in my above numbered patent.

Various modifications may be made in the -bination with a body portioncomprising a pressing member having a groove in the upper surface thereof, a tubular heating ele- Ament located therein, and terminal pins for said heating element, of means for supporting said terminal pins in proper operative relation relatively to the body portion, said means having a depending peripheral flangev portion for directly engaging and' compressively holding said heating element in thermally conductive relation in said groove.

3. -Iu an electricall heated device, the combination with a bo y portion comprising a pressingl member having a. peripheral groovein the upper surface thereof, means w located in said groove for heating said pressing member comprising a resistor member enclosed within a tubeof highly conductive metal and insulated therefrom, and terminal Y members for said heating element, of means having adepending peripheral portion for supporting said terminal members in proper operative position relatively to said body portion, the edge of the depending eripheral portion directly engaging the tu e of the heating means for compressivel holding it in thermally conductive relation in v said groove."

4. In an electricall combination with abo y portion comprising a pressing member having a peripheral groove .in the u PPer sklffa@ thelfcf, .0f

heated device, the l lmeans located in said groove for heating said pressing casting comprising a preshaped vresistor member enclosed within a sheathJ Vof expansively oxidizable .materiaha tube enclosing said resistor and sheath whereby said resistor is electrically insulated from, and compressively held in, thermally-conductive relation therewith, terminal members for the resistor, a thermally actuable switch associated with-said resistor for maintaining the temperature of the bottom surbination with a body portion comprising a` pressing member having a peripheral groove of substantially U-shape in the upper surface and a partially circular depression, a tubular member enclosing an electric resistor and insulated therefrom located in said groove, a thermally-actuable means electrically associated with said heating element and located in said partially circular depression, and terminals for said resistor, of a single member having depending portions thereon which support said terminals and press said thermally-actuable means in to close thermalA relation withl the aforesaid body' portion.

6; In van electrically heated device, the combination with a body portion compris'- ing a pressing member having a peripheral groove and a substantially circular depression in the top surface thereof, a tubular lheating element located in said peripheral groove, a thermally actuable switch electrically associated with said heating element :efr

and disposed within said circular depression in thermal relation with said pressing casting, and terminals for said heating element, of a single member having a depending peripheral portion and an intermediate depending portion, the edge of the depending peripheral portion pressing said tubular element into operative relation with said body portion and the intermediate depending porltion pressing the switch into the4 substantially circular depression.

7. In an electrically heated device, the combination with a bodyportion comprising a heating element, terminal members, a thermally actua-ble control switch electrically associated with said heating element and thermally associated with the body portion, of a single clamping member for supporting the terminals and for pressing4 the switch inA proper operative relation with said vbody portion.

In testimony whereof, I have hereunto subscribed my name this 22nd day of May,

lCHRIsrIAN B. BACKER. 

